Oral diseases cause premature loss of chewing function in many middle-aged and elderly people, and may also cause or aggravate heart disease, gastric disease, diabetes, cardiovascular disease, and joint disease. Many dental diseases have become far more harmful than the teeth themselves and are an important cause of many diseases. What can cause premature loss of chewing function? Oral diseases in middle-aged and elderly people impair the function of the oral chewing system. Looking around us, even among the middle-aged and elderly people in their fifties and sixties, many of them have not had enough functional teeth for 20 long ago, that is, they are not very old and have lost all their teeth. At present, the oral diseases of middle-aged and old people are mainly reflected in three major aspects: caries, periodontal disease and tooth loss and abrasion. 1, caries: middle-aged and old people have more rotten teeth, especially root surface caries. Root surface caries is often not easy to find because of the hidden location, once found, it is more serious, and many of them will cause tooth nerve pain. Periodontal disease: The early symptoms of periodontal disease are not easy to attract attention, resulting in long-term chronic infection of periodontal tissues and recurrent inflammation, and the condition is quite serious when patients visit the clinic, which not only damages the function of oral chewing system, but also seriously affects the whole body health. 3, dental defects and wear: middle-aged and elderly teeth after decades of use, some will be due to bad habits such as long-term use of hard-bristled large-headed toothbrush horizontal brush or love to bite hard objects or eat acidic food, resulting in dental defects such as occlusal surface wear, so that the teeth chewing function is reduced, such as not taking effective protective measures, will make the loss of functional teeth faster and more.